Fluid flow control device



FLUD FL?! CONTROL DEVICE 2 Sheets-shew l Filed NOV'. 20, 1944 Awww@ D. H. ANNN FLUID FLOW CONTROL DEVICE ,2 Sheets-511%?. 2

Filed Nov. 20

atente 2,433,414 y FL FLOW CUNTROL DEVIE Douglas H. Armin, Uahland, Calif., assigner to Fluid Control Engineering Co., Pieont, Salif.,

a oopartnership Application November 2li, 1944, Serial No. 564,229

2 Claims.

This invention relates generally to fluid ow control devices of the type in which the positioning of valve elements is controlledby fluid pressure upon a diaphragm.

It is an object of the invention to vprovide a device of the` above character having a relatively small ow capacity but which will give reliable and sensitive response over a wide range of applied pressures.

Another object o the invention is to provide a ow controi device of the above character which is particularly adapted for use as a pilot valve for such operations as the automatic control of a main valve.

A f urther object of the invention is to provide a valve of the above character having a relatively simple and mechanical construction. and which by simple shifting of certain parts can be adapted to a variety of operations.

Additional objects of the invention will appear from the following description in which the preferred embodiments have been set forth in detail in conjunction with the accompanying drawing.

Referring to the drawing:

Fig. 1 is a side elevational view in section, illustrating a valve incorporating the present' inven-` tion, and also diagrammatically showing connections which can be made between such a valve and a main valve.

Fig. 2 is a longitudinal cross-sectional View taken along the line 2 2 of Fig. l.

Fig. 3 is a side elevational view in section, illustrating a change in the positioning of certain parts to adapt the device for use to provide automatic back pressure control.

Fig. 4. is a side elevational view in section showing a modiiled arrangement of diaphragms for the device. A

.That form of the invention illustrated in Fig. l consistsfof a body formed mainly of the body parts Ita, Ilib and Ic. Part ida is in the form of a bonnet for housing the loading spring II. Part Ib servesto mount and space two operating diaphragms, while part Ille is an end closure plate.

The loading spring I I within the bonnet Ita has one end seated upon a thrust disc I2, and its other end seated upon the thrust member I3, which as will be presently explained applies loading force to the movable valve element. In order toadjust the loading force the disc l2 is seated upon the inner end of an adjustable screw threaded in one end of the bonnet.

Between the bonnetand the end plate I c there (Ci. Sli- 23) are in this instance three diaphragrns it, ll and i8. These diaphragme are clrcularly contoured and have their peripheral edge portions engaged by mounting means. They are disposed in spaced parallel relationship and are at right angles to a common central axis. It is preferable to form these diaphragms of relatively thin flexible sheet metal, such as stainless steel, phosphor bronze, or the like.

The peripheral edge portion o diaphragm l@ is shown clamped between one end of the body part lb, and a. spacer ring 2i ,disposed between body wb and the adjacent portion of the vbonnet ma. In this connection note that body part lib is cylindrically shaped. The peripheral edge of diaphragm il is clamped between the other end of the body part Illb and a spacer ring 22, the latter being interposed between the body part im) and the end plate Ilic. Diaphragm It is in turn interposed and clamped between ring 22 and end plate Iilc. i

Mounting means for one of the valve elements is formed byv a member 23, which can be shaped substantially as illustrated, and which has its ends suitably attached to the central portions of the diaphragme i6 and Il. Thus a stud 2d is accommodated withinv a central opening in diaphragm I6, and is threaded into the adjacent end of member 23. A generally similar stud 2E is accommodated within an opening in diaphragm il and is threaded into the adjacent end of member 23. The annular face 2l of stud 2t is preferably convexly curved as illustrated, as for example to correspond with the surface of a sphere, lin order to accommodate exing movements of the diaphragm I6 without causing bending of the diaphragm over sharp edges. This stud is also shown provided with a spherically shaped surface 23. adapted to form an abutment with a similarly formed concave surface 29 on the thrust member I3. Stud 26 is likewise formed with curved surfaces 3i and 32, the latter forming a convex surface for abutment with diaphragm I8.

The valve member carried by the means connecting the diaphragms I6 and I'I, is in this in- \stance an element 33 in the form of a semi- 3 The second valve element, which cooperates with element 33. is in the form of a seat 38 which has a port or orifice 38 through the same. This seat is threaded into or otherwise suitably at' serving to connect the oriiice 38 with a vconnecting pipe 44.

The space 48 surrounding member 23 is shown connected with pipe 41. A third pipe 48 is shown connecting to the space 43 on one side of the diaphragm I8. A suitable vent 5I can be provided for venting the space between diaphragms I1 and v I8 to the atmosphere. A suitable vent 52 is also A feature of the device described above is that certain parts are reversible. to make it possible to adapt the device for diiferent types of operation, as for example as a part of back pressure regulating apparatus. Fig. 3 illustrates a change in the positioning of certain of the parts so that the device is capable of operating in apparatus for automatic back pressure regulation. Thus the valve member 33 has been removed from the socket or bore 38. and has been loosely fitted in the socket or bore 1I provided in the upper stud 24.' Body part I 0b has been inverted or turned end for end, so that the seat ring 38 now cooperates with the I valve member 33. Fig. 3 shows suitable pipe conprovided for maintaining the space Within bonnet Illa at atmospheric pressure.

The device described above can be used in various ways. Assuming application of iluid pressure to the pipe 44, it will be evident that application of iiuid pressure to pipe 48 serves to urge the three diaphragms against the loading spring II and in a direction to maintain the valve elements closed. Upon lowering the pressure applied to pipe 48 below a predetermined value, the loading spring forces the valve element 33 downwardly as viewed in Fig. l, thus permitting fluid from pipe 44 to escape into space 48. Any pressure in space 46 is balanced out because it acts upon equal pressure areas provided with diaphragms i8 and I1.

One manner in which the device can be used to control a main valve has been illustrated diagrammatically in Fig. 1. Y The main valve M in this instance consists of a iiuid operated dia.-` phragm 58 with iiuid chambers 51 and 58 above and below the same. The diaphragm is directly connected to the valve member 53, which controls flow oi fluid between the inlet and outlet passages 8| and 82. Line 83 serves to connect chamber 51 with the pipe 44.A Line 84 serves to connect the chamber 58, through the ow restricting orifice 88, to the pipe 44. Pipe 81 connects the outlet passage 82 with both the pipes .41 and 43. Chamber 58 in this instance is in free communication nections for connecting the device with a main valve M, whereby the combination serves as an automatic back pressure regulator. Thus line 12 connects pipe "and the chamber 48 to the outlet passage 13 of the main valve. Line 18 connects pipe 48 and pressure chamber 48. with the inlet passage 11 of the main valve. Line 18 connects pipe 44 to the chamber 81 above the diaphragm of the main valve. The inlet passage 11 of the main valve is alsol connected vby line 13, through flow restricting oriiice 8|. to the line 18 and to the chamber 51.

Assuming that the outlet passage 13 is connected to a low pressure system or is vented to the atmosphere, a gas pressure system connected to the inlet 11 can be automatically regulated by controlled venting through the vmain valve M when the inlet pressure reaches and tends to exceed a desired pressure level. Thus when the pressure in passage 11 exceeds a predetermined value for which the loading spring II is set, diaphragm I8 is urged upwardly to cause opening movement of the valve member 33 with respect to the seat 38. This permits increased flow through line 18, which because of the flow restricting oriiice 8|, causes a drop in the pressure maintained Thus diaphragm 38 flexes upin chamber 51. wardly to open or to increase the rate of iiow through the mainvalve.

The feature of adaptability described above is made possible because of the manner in which the valve member 33 can be placed in-either one of its with the inlet passage 8l, and therefore connection of line 84 with the chamber 58 is the same as a connection to` the inlet side.

With the connections to a main valve as described above, the apparatus operates as an automatic pressure reducing regulator for air or' other gas. The tension on the loading spring is set'in accordance with the pressure which it is desired to maintain within the outlet 82. The inlet 8I connects with a suitable source of gas at a substantially higher pressure. Should the pressure in outlet 62 drop below the desired value, the diaphragms are iiexed downwardly as viewed in Fig. l, thus permitting an increased flow of gas through pipe 44 by virtue of greater separation of the valve elements. Increased ilo'w of gas through pipe 44, because of the flow restricting oriiice 88, results in a drop in pressure within the line 83 and chamber 51, thus lpermitting the inlet pressure in chamber 58 to urge the diaphragm 58 upwardly to further` open the main valve 58. Conversely if the pressure in outlet 82 increases beyond a desired level, then reverse operations take place, that is there is a closing between the elements 33 4and 38, accompanied by decreased flow of duid through pipe 44, thus causing a greater pressure to be built up in chamber 51 to urge the valve member 58 closer to its seat.

two operating positions. and because of the way in which the body part 10b can be inverted or turned end for end. to cooperate with either position of member 33. It will be noted that valve member 33 together with seat 38 is aligned with the central common axis of the diaphragms I8 and I1. Likewise member 23 is retained in proper alignment solely by virtue of its connection with the diaphragms I8 and I1. This makes for 'frictionless movement of the operating parts, while at the same time bushings.

'I'he arrangement of diaphragms canbe varied v 1erated member for moving the valve member 33 between open and closed positions. An arrangement of this sort has been illustrated in Fig. 4.

Thus in this instance diaphragm I8 is omitted in entirety, and diaphragm I1 has been perforated. With this arrangement pressure of gas in chamber 48 acts upon diaphragm I8 in a direction to urge the same upwardly. Assuming that pipes 44 and 48 constitute inlet and outlet respectively,

with pipe 44 connected to a source of iluid -under pressure, the device will operate as a small capacity automatic pressure reducing valve. Buchan eliminating conventional guide v assembly can also be utilized together with a mainv valve for various operations such as automatic pressure reduction.

I claim: 1. In a valve for control of uid ilow, a pair oi flexible diaphragms, means forming a valve body serving to mount the diaphragms in spaced parallel relationship and in axial alignment, a pair of cooperating valve elements, one forming a valve member and the other forming a ported valve seat adapted to be engaged bythe valve member to close the port, a rigid mounting means for said valve member having spaced end portions of the same rigidly'attached to the central portions of the diaphragms to support said mounting means for movement in opposite directions along the common axis oi the diaphragms, said mountingl means `having spaced and oppositely faced portions of the same adapted to position and retain said valve member in either one of two operating locations, a portion of the valve body comprising a body part positioned between the two diaphragms and reversible end for end in either one of two operating positions, and a member secured 4to said last named body part and extending inwardly of ythe same with its inner end disposed between the two locations of the valve member. the inner end of said extension serving to support the valve seat for cooperation with thev valve member.

2. In a valve for control of uid flow. a.v pair of iiexible diaphragms, means forming a valve body serving to mount the diaphragme in spaced parallel relationship 'and in axial alignment, a

pair oi cooperating valve elements; one forming a valve member and the other forming a ported valve seat adapted to-be engaged by the valve member to close the ports, a rigid mounting means for said valve member having oppositely faced end portions of the same adapted to receive and retain said valve member, a pair of duplicate members serving to attach said end portions of the mounting to said diaphragms for movement in opposite directions along the common axis of the diaphragms, a portion of the valve body comprising a body part positioned between the two diavalve member.

l DOUGLAS H. ANNIN.

REFERENCES CIITED The following references are of record in the file ol this patent:

UNITED STATES PATENTS Number Name Date 1,733,432 Slinger Oct. 29, 1929 796,959 Croslen Aug. 8, 19M 

